Debt (ABL Facility) - Additional Information (Detail) - ABL Facility [Member]	12 Months Ended
Dec. 31, 2016 USD ($)
Minimum [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio	100.00%
Maximum [Member]
Debt Instrument [Line Items]
Description of threshold with lenders' commitments	10.00%
Facility amount with lenders commitments	$ 37,500,000
Percentage of lender commitment under revolving credit facility	10.00%
Amount eligible for condition for excess availability of credit	$ 37,500,000

Amount of lender commitments for cash dominion provision threshold.

No definition available.

Name:	cot_AmountOfLenderCommitmentsForCashDominionProvisionThreshold
Namespace Prefix:	cot_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of lender commitments for minimum fixed charge coverage ratio threshold.

+ References

No definition available.

+ Details

Name:	cot_AmountOfLenderCommitmentsForMinimumFixedChargeCoverageRatioThreshold
Namespace Prefix:	cot_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

Fixed charge coverage ratio.

+ References

No definition available.

+ Details

Name:	cot_FixedChargeCoverageRatio
Namespace Prefix:	cot_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of lender commitment under revolver for cash dominion provision threshold.

+ References

No definition available.

+ Details

Name:	cot_PercentageOfLenderCommitmentUnderRevolverForCashDominionProvisionThreshold
Namespace Prefix:	cot_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of lender commitment under revolver for minimum fixed charge coverage ratio threshold.

+ References

No definition available.

+ Details

Name:	cot_PercentageOfLenderCommitmentUnderRevolverForMinimumFixedChargeCoverageRatioThreshold
Namespace Prefix:	cot_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: